Allbirds is a San Francisco-based direct-to-consumer footwear brand that specializes in making sustainable sneakers and casual shoes. In 2014, founders Tim Brown and Joey Zwillinger launched the brand’s first product, a sneaker made from wool. In March 2018, the brand developed a sneaker made from eucalyptus fibers, which were the first-ever shoes to receive certification from the Forestry Stewardship Council. Allbirds also invented a foam derived from sustainably sourced sugar cane (rather than fossil fuels). This material, which Allbirds calls SweetFoam, was introduced in a flip-flop in August 2018, and will be used to form the soles of all shoes going forward. Allbirds made the recipe for this eco-friendly foam open source to encourage other footwear companies to use the material in their own supply chains. Allbirds has been slowly expanding its retail footprint, with a plan to have a network of 10 stores in the United States, the United Kingdom, and New Zealand by 2019. In October 2018, the company raised a $50 million Series C round, bringing its valuation to $1.4 billion.